From: 王贇 <yun.wang@linux.alibaba.com>
To: Paul Moore <paul@paul-moore.com>,
"David S. Miller" <davem@davemloft.net>,
Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
David Ahern <dsahern@kernel.org>,
Jakub Kicinski <kuba@kernel.org>,
netdev@vger.kernel.org, linux-security-module@vger.kernel.org,
linux-kernel@vger.kernel.org
Subject: [PATCH] net: fix NULL pointer reference in cipso_v4_doi_free
Date: Thu, 26 Aug 2021 11:42:42 +0800 [thread overview]
Message-ID: <c6864908-d093-1705-76ce-94d6af85e092@linux.alibaba.com> (raw)
In netlbl_cipsov4_add_std() when 'doi_def->map.std' alloc
failed, we sometime observe panic:
BUG: kernel NULL pointer dereference, address:
...
RIP: 0010:cipso_v4_doi_free+0x3a/0x80
...
Call Trace:
netlbl_cipsov4_add_std+0xf4/0x8c0
netlbl_cipsov4_add+0x13f/0x1b0
genl_family_rcv_msg_doit.isra.15+0x132/0x170
genl_rcv_msg+0x125/0x240
This is because in cipso_v4_doi_free() there is no check
on 'doi_def->map.std' when 'doi_def->type' equal 1, which
is possibe, since netlbl_cipsov4_add_std() haven't initialize
it before alloc 'doi_def->map.std'.
This patch just add the check to prevent panic happen for similar
cases.
Reported-by: Abaci <abaci@linux.alibaba.com>
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
---
net/ipv4/cipso_ipv4.c | 18 ++++++++++--------
1 file changed, 10 insertions(+), 8 deletions(-)
diff --git a/net/ipv4/cipso_ipv4.c b/net/ipv4/cipso_ipv4.c
index 099259f..7fbd0b5 100644
--- a/net/ipv4/cipso_ipv4.c
+++ b/net/ipv4/cipso_ipv4.c
@@ -465,14 +465,16 @@ void cipso_v4_doi_free(struct cipso_v4_doi *doi_def)
if (!doi_def)
return;
- switch (doi_def->type) {
- case CIPSO_V4_MAP_TRANS:
- kfree(doi_def->map.std->lvl.cipso);
- kfree(doi_def->map.std->lvl.local);
- kfree(doi_def->map.std->cat.cipso);
- kfree(doi_def->map.std->cat.local);
- kfree(doi_def->map.std);
- break;
+ if (doi_def->map.std) {
+ switch (doi_def->type) {
+ case CIPSO_V4_MAP_TRANS:
+ kfree(doi_def->map.std->lvl.cipso);
+ kfree(doi_def->map.std->lvl.local);
+ kfree(doi_def->map.std->cat.cipso);
+ kfree(doi_def->map.std->cat.local);
+ kfree(doi_def->map.std);
+ break;
+ }
}
kfree(doi_def);
}
--
1.8.3.1
next reply other threads:[~2021-08-26 3:42 UTC|newest]
Thread overview: 25+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-08-26 3:42 王贇 [this message]
2021-08-27 0:09 ` [PATCH] net: fix NULL pointer reference in cipso_v4_doi_free Paul Moore
2021-08-30 10:20 ` 王贇
2021-08-30 10:14 ` 王贇
2021-08-30 10:28 ` [PATCH v2] " 王贇
2021-08-30 11:30 ` patchwork-bot+netdevbpf
2021-08-30 14:17 ` Paul Moore
2021-08-30 16:45 ` Jakub Kicinski
2021-08-30 16:50 ` Paul Moore
2021-08-31 2:41 ` 王贇
2021-08-31 13:48 ` Paul Moore
2021-09-01 1:51 ` 王贇
2021-09-01 9:30 ` David Miller
2021-09-01 9:41 ` 王贇
2021-09-01 10:45 ` David Miller
2021-09-02 3:04 ` 王贇
2021-09-01 2:18 ` [PATCH] Revert "net: fix NULL pointer reference in cipso_v4_doi_free" 王贇
2021-09-01 2:21 ` 王贇
2021-09-01 21:05 ` Paul Moore
2021-09-02 2:37 ` 王贇
2021-09-03 2:15 ` Paul Moore
2021-09-03 2:31 ` 王贇
2021-09-03 14:08 ` Paul Moore
2021-09-03 2:27 ` [PATCH] net: remove the unnecessary check in cipso_v4_doi_free 王贇
2021-09-03 14:08 ` Paul Moore
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